Nyob rau hauv cov txheej txheem ntawm PCBA ua tiav, kev xaiv ntawm PCBA tin kev nkag mus kuj tseem ceeb heev. Nyob rau hauv cov txheej txheem los ntawm lub qhov, tsis zoo tin nkag ntawm PCB pawg thawj coj tau yooj yim tuaj yeem ua rau muaj teeb meem xws li cam pob qij, txhawm rau txhawm thiab txawm poob.
Peb yuav tsum paub ob lub ntsiab lus no hais txog PCBA tin kev nkag mus
1、 Qhov yuav tsum muaj ntawm PCBA tin kev nkag siab
Raws li IPC tus qauv, qhov yuav tsum tau ntawm PCBA tin kev nkag mus los ntawm qhov-qhov cam qev sib koom ua ke feem ntau ntau dua 75%. Uas yog hais, tus txheej txheem ntawm cam nkag mus ntawm PCBA yog tsis tsawg tshaj li 75% ntawm aperture qhov siab (phaj tuab) nyob rau hauv kev soj ntsuam ntawm qhov chaw ntawm welded, thiab nkag mus ntawm PCBA yog tsim nyog nyob rau hauv ntau ntawm 75% - 100 %. Txawm li cas los xij, thaum lub qhov-txuas nrog rau lub tshav kub dissipation txheej lossis cov txheej txheem kub kom sov, ntau dua 50% ntawm PCBA tin kev nkag mus yuav tsum muaj.
2、 Qhov cuam tshuam cuam tshuam tin permeation ntawm PCBA
Txoj kev tsis zoo ntawm kev nkag mus ntawm PCBA feem ntau yog cuam tshuam los ntawm cov khoom, yoj soldering txheej txheem, flux thiab phau ntawv vuam.
Yam tseem ceeb uas cuam tshuam rau tin permeation ntawm PCBA tau tshawb xyuas
1. Cov Khoom Siv
Lub siab kub yaj ua muaj lub zog tsis muaj zog, tab sis tsis yog txhua tus hlau (PCB pawg thawj coj, Cheebtsam) tuaj yeem nkag mus rau, xws li txhuas, nws cov nplaim feem ntau yuav ua rau txheej txheej tiv thaiv tuab, thiab cov qauv sab hauv molecular kuj ua rau nws nyuaj rau lwm yam lwg me nkag. Thib ob, yog tias muaj txheej txheej oxide nyob saum npoo ntawm hlau yuav tsum tau welded, nws tseem yuav tiv thaiv kev nkag mus ntawm cov lwg me me. Peb feem ntau siv kev kho flux, lossis daim ntaub nyias nyias txhuam kom huv.
2. Wave soldering txheej txheem
Txoj kev tsis zoo ntawm kev nkag mus ntawm PCBA yog cuam tshuam ncaj qha rau cov txheej txheem nthwv dej soldering. Rov ua kom zoo dua lub vuam tsis xws li yoj qhov siab, kub, vuam sijhawm lossis txav ceev. Ua ntej tshaj plaws, lub kaum sab xis ntawm txoj kev tsheb nqaj hlau yuav tsum raug txo kom zoo, thiab qhov siab ntawm nthwv dej yuav tsum tau nce ntxiv los txhim kho tus neeg sib tiv tauj ntawm cov kua yajthem thiab qhov kawg; tom qab ntawd, qhov kub ntawm yoj soldering yuav tsum tau nce. Feem ntau hais lus, qhov kub dua yog, qhov muaj zog permeability ntawm tin yog. Txawm li cas los xij, cov kabmob kub ntawm lub Cheebtsam yuav tsum tau coj mus rau hauv tus lej. Thaum kawg, qhov nrawm nrawm ntawm cov khoom siv conveyor tuaj yeem txo qis thiab preheating thiab vuam lub sijhawm tuaj yeem nce ntxiv kom ua rau flux tag nrho tshem tawm ntawm oxidation Qhov kev sib koom ua ke yog ntub thiab kom cov xoob tau nce.
3. Flux
Flux tseem tseem yog qhov tseem ceeb cuam tshuam rau qhov tsis zoo ntawm kev nkag mus ntawm PCBA. Flux ua lub luag haujlwm ntawm tshem cov oxide ntawm PCB sab nraud thiab cov khoom siv thiab tiv thaiv kev txhim kho reoxidation thaum vuam. Kev xaiv tsis zoo ntawm flux, txheej tsis sib xyaw thiab dhau ntawm cov flux tsawg dhau yuav ua rau kom cov raj tsis zoo. Lub flux ntawm cov hom lag luam zoo tuaj yeem xaiv, qhov ua kom lub zog thiab ntub dej nyhuv yuav siab dua, uas tuaj yeem tshem cov oxide uas nyuaj rau tshem; kos lub flux nozzle, lub tog tsis muaj zog yuav tsum tau hloov nyob rau hauv lub sijhawm, kom paub tseeb tias PCB lub rooj tsavxwm saum npoo yog coated nrog tus nqi tsim nyog ntawm flux, thiaj li ua si cov nyhuv soldering ntawm flux.
4. Kev tuav vuam
Hauv qhov tseeb plug-in vuam zoo soj ntsuam, feem ntau ntawm cov hlau txuas tsuas muaj qhov chaw ntawm cov npoo ua lub khob hliav qab, tab sis tsis muaj tin nkag mus hauv los ntawm lub qhov. Hauv kev ntsuam xyuas kev ua haujlwm, nws tau paub tseeb tias ntau qhov ntawm cov no yog cuav soldering, uas feem ntau muaj nyob rau hauv phau ntawv ntsaws, vim tias cov hlau kub kub tsis tsim nyog thiab lub sijhawm vuam yog luv heev. Nws yog ib qho yooj yim los nce tus nqi kho kom zoo vim txoj kev tsis zoo ntawm PCBA. Yog tias qhov yuav tsum tau ntawm PCBA tin kev nkag mus yog qhov siab thiab lub vuam zoo yog nruj, xaiv yoj soldering tuaj yeem siv, uas tuaj yeem txo cov teeb meem tsis zoo ntawm qhov tsis txaus sab hauv PCBA.
